(477c) Comparative Study of Hydrothermal and Nades-Assisted Deconstruction of Transgenic Crops for Enhanced Recovery of Lipids and Sugars
AIChE Annual Meeting
2023
2023 AIChE Annual Meeting
Forest and Plant Bioproducts Division
Biomass Characterization, Pretreatment, and Fractionation I
Wednesday, November 8, 2023 - 8:36am to 8:54am
In view of this, hydrothermal and natural deep eutectic solvents (NADES) pretreatment potential were assessed for the deconstruction of genetically engineered bioenergy crops for their feasibility for high sugar and lipid recovery. Hydrothermal pretreatment is one of the mildest methods, which uses hot water at a relatively low temperature (up to 230 °C) and low pressure [8]. Hydrothermal pretreatment selectivity hydrolyses the hemicellulose fraction to xylose, arabinose and glucose and simultaneously generates a certain amount of degraded products such as furfural, HMF, formic acid etc., which can limit the enzymatic saccharification of lignocellulosic biomass [9]. On contrary, NADES is a combination of hydrogen bond donor (HBD) and hydrogen bond acceptor (HBA), with exceptional solvent characteristics, an alternative to conventional organic solvents and benefits with easy preparation, low toxicity, high biodegradability, and high fractionation efficiency. NADES can act as adjuvants for weakening the lignin-carbohydrate recalcitrance matrix at the desired temperature of 100 to 160 °C and pretreatment circumstances while enhancing lignin solubilization and could attribute to enhanced digestibility of pretreated biomass towards cellulases.
Thus, several choline chloride-based NADES were prepared using bio-derived precursors, i.e., lactic acid by varying the molar ratio of HBD and HBA (1:1, 1:2) at 60 to 80 °C and were employed for the pretreatment of transgenic oilcane bagasse, and miscanthus for the fractionation of lipids and carbohydrates. A comparative study between hydrothermal pretreatment and NADES-assessed pretreatment was conducted in terms of compositional analysis, toxins generation, chemical input, severity effect, lignin removal and overall sugar and lipid recovery from pretreated oilcane, and miscanthus biomass. The initial study showed that the suitable eutectic combination of NADES, i.e., choline chloride and lactic acid in a 1:2 molar ratio, prepared at 60-80 °C, could effectively solubilize >75% lignin, while enabling high biomass digestibility (>85%) during enzymatic saccharification, and enhance lipid recovery (>60%). In a separate experiment, hydrothermal pretreatment optimization was investigated with varying pretreatment temperatures (170-210 °C), with a residence time of 10-20 min and was compared with NADES pretreatment in terms of toxins release, glucan/ xylan recovery, lignin solubilization, crystallinity reduction, enzymatic accessibility, lipid recovery etc. Hydrothermal pretreatment of oilcane bagasse followed by enzymatic saccharification resulted in a 2-fold increase in total lipids with improved enzymatic digestibility of >75%. These findings lead to an economical an environmentally friendly method to process genetically engineered crops for selective fractionation of lipids and sugars, and would aid in developing a sustainable biorefinery platform for the co-production of biodiesel and bioethanol.
Keywords: Natural deep eutectic solvents; hydrothermal pretreatment, transgenic crop, lipids, sugar, extraction
References:
- Parajuli, S., et al., Towards oilcane: Engineering hyperaccumulation of triacylglycerol into sugarcane stems. GCB Bioenergy, 2020. 12(7): p. 476-490.
- Kumar, D., et al., Techno-economic feasibility analysis of engineered energycane-based biorefinery co-producing biodiesel and ethanol. GCB Bioenergy, 2021. 13(9): p. 1498-1514.
- Jia, Y., S. Maitra, and V. Singh, Chemical-free production of multiple high-value bioproducts from metabolically engineered transgenic sugarcane âoilcaneâ bagasse and their recovery using nanofiltration. Bioresource Technology, 2023. 371: p. 128630.
- Maitra, S., et al., Bioprocessing, Recovery, and Mass Balance of Vegetative Lipids from Metabolically Engineered âOilcaneâ Demonstrates Its Potential as an Alternative Feedstock for Drop-In Fuel Production. ACS Sustainable Chemistry & Engineering, 2022. 10(50): p. 16833-16844.
- Cortés-Peña, Y.R., et al., Economic and Environmental Sustainability of Vegetative Oil Extraction Strategies at Integrated Oilcane and Oil-Sorghum Biorefineries. ACS Sustainable Chemistry & Engineering, 2022. 10(42): p. 13980-13990.
- Cortés-Peña, Y.R., et al., Economic and Environmental Sustainability of Vegetative Oil Extraction Strategies at Integrated Oilcane and Oil-Sorghum Biorefineries. ACS Sustainable Chemistry and Engineering, 2022. 10(42): p. 13972-13979.
- Raj, T., et al., Lignocellulosic biomass as renewable feedstock for biodegradable and recyclable plastics production: A sustainable approach. Renewable and Sustainable Energy Reviews, 2022. 158: p. 112130.
- Deshavath, N.N., et al., A Chemical-Free Pretreatment for Biosynthesis of Bioethanol and Lipids from Lignocellulosic Biomass: An Industrially Relevant 2G Biorefinery Approach. Fermentation, 2023. 9(1).
- Singh, R., et al., Hydrothermal pretreatment for valorization of genetically engineered bioenergy crop for lipid and cellulosic sugar recovery. Bioresource Technology, 2021. 341.